This study aims to determine whether combining aggressive intravenous hydration with indometacin is more effective at preventing pancreatitis after a Extracorporeal Shock Wave Lithotripsy (ESWL) than using indometacin alone.

The study will involve patients who are scheduled to undergo ESWL for pancreatic stones. Participants will be randomly assigned to one of two groups: one will receive both the intravenous hydration and the rectal indometacin, while the other will receive only the rectal indometacin.

The trial will be conducted at multiple centers, ensuring a broad and diverse patient population.

The primary outcome of the study will be the incidence of pancreatitis after the ESWL procedure.

This study is important because it could lead to a better understanding of how to prevent pancreatitis after ESWL, potentially improving patient outcomes and reducing the risk of serious complications.

Inclusion Criteria:

• Patients with painful chronic pancreatitis eligible for P-ESWL treatment
• Ages between 18-85 years
• Providing informed consent

Exclusion Criteria:

• Patients readmitted to the hospital for ESWL during the study period
• contraindications to ESWL
• Signs of congestive heart failure, such as pitting edema or a New York Heart Association classification greater than class I heart failure. For patients ≥ 70 years old, brain natriuretic peptide (BNP) and cardiac ultrasound would be performed before ESWL. Patients with BNP>100pg/ml or Ejection Fraction value<50% should be excluded
• Respiratory insufficiency (pO2 < 60 mmHg or saturation < 90% despite FiO2 of 30% or requiring mechanical ventilation). For patients ≥ 70 years old, pulmonary function tests would be performed before ESWL. Patients with Forced Expiratory Volume in the first second (FEV1) <70% are excluded
• Patients receiving more than 1.5 mL/kg/h or 3 L/24 h of intravenous fluids in the 24 h before ESWL
• Hypotension (systolic blood pressure <90 mmHg or mean arterial pressure <70 mmHg)
• Hypo- or hypernatremia (serum Na+ levels < 130 or > 150 mmol/L)
• Severe liver disease (cirrhosis with ascites, liver abscess)
• receiving NSAIDs within 7 days
• Contraindications for rectal use of NSAIDs (renal dysfunction with serum creatinine >120 μmol/L, allergy, active gastrointestinal bleeding, ulcer disease, and NSAID use for other indications [other than cardioprotective aspirin])
• presence of coagulopathy or received anticoagulation therapy within 3 days
• acute pancreatitis within 3 days
• known active cardiovascular or cerebrovascular disease
• pregnant or breastfeeding women
• without a rectum (ie, status post-total proctocolectomy)